1. Perinatology Committee, Japan Society of Obstetrics and Gynecology Tokyo Japan
2. Department of Obstetrics & Gynecology Hamamatsu University School of Medicine Hamamatsu Japan
3. Department of Maternal Fetal Medicine Osaka Women's and Children's Hospital Osaka Japan
4. Department of Obstetrics and Gynecology Keio University School of Medicine Tokyo Japan
5. Department of Obstetrics and Gynecology International Catholic Hospital Tokyo Japan
6. Department of Obstetrics and Gynecology Juntendo University Faculty of Medicine Tokyo Japan
7. Department of Obstetrics and Gynecology Juntendo University Urayasu Hospital Urayasu Japan
8. Department of Obstetrics and Gynecology Yokohama City University Graduate School of Medicine Yokohama Japan
9. Shirota Obstetrical and Gynecological Hospital Zama Japan
10. Department of Obstetrics and Gynecology Kawasaki Medical School Kurashiki Japan
11. Department of Obstetrics and Gynecology Mie University Graduate School of Medicine, Tsu Japan
12. Shizuoka College of Medicalcare Science Hamamatsu Japan